Stethoscope having microphone therein

ABSTRACT

A stethoscope chestpiece is disclosed having an acoustic-to-electrical transducer residing within the acoustic pathway of the chestpiece. The transducer resides within a mounting that can provide shock attenuation and vibration isolation. The transducer preferably resides within a coaxial position in the acoustic pathway. The chestpiece is useful in a stethoscope which can be electrically connected to auscultation systems.

FIELD OF THE INVENTION

The present invention relates generally to stethoscopes and, moreparticularly, to chestpieces for stethoscopes, especially acousticstethoscopes having transducers mounted in the chestpiece.

BACKGROUND OF THE INVENTION

Stethoscopes have long been used by physicians to monitor auscultatorysounds. Typically, stethoscopes have been comprised of a chestpiece, asound transmission mechanism and an earpiece assembly. The chestpiece isadapted to be placed against the skin of a patient for gathering theauscultatory sounds. The sound transmission mechanism acousticallytransmits the gathered sound to the earpiece where the physician maymonitor the sound.

The chestpiece of conventional acoustic stethoscopes typically is dualsided, top and bottom, to allow either side of the chestpiece to contactthe skin of the patient, perhaps for the gathering of auscultatorysounds in different frequency ranges.

The art of auscultation is becoming more sophisticated through the useof electrical or electronic sensors, information processors, andinformation display. The use of an acoustic stethoscope is a welldeveloped skill that can be enhanced with various forms of electronicamplification, signal processing, and signal display. Two examples ofauscultation devices are disclosed in U.S. Pat. No. 5,010,889 (Bredesenet al.) and pending U.S. patent application Ser. No. 07/782,079(Bredesen et al.), now U.S. Pat. No. 5,213,108.

Provision for both acoustic and electrical accumulation of sound at astethoscope chestpiece has been attempted.

U.S. Pat. No. 4,071,694 (Pfeiffer) describes a stethoscope chestpiecewhich has both an electronic and an acoustic capability. The chestpieceof the stethoscope described therein has a microphone mounted in alocation adjacent to the acoustic pathway and is sealed into an internalair channel of the chestpiece.

U.S. Pat. No. 4,362,164 (Little et al.) describes a stethoscopechestpiece where the microphone is positioned in a cavity diametricallyopposed to the acoustic pathway.

Copending, co-assigned U.S. patent application Ser. No. 07/658,099, nowU.S. Pat. No. 5,204,500, describes an ergonometric stethoscopechestpiece where the microphone is mounted in a pathway different fromthe acoustic pathway.

SUMMARY OF THE INVENTION

The present invention provides a stethoscope having a chestpiece wherethe transducer resides within the acoustic pathway in the chestpiece.

The stethoscope chestpiece of the invention comprises a stethoscopehousing forming an acoustic pathway and a transducer residing within theacoustic pathway.

The stethoscope of the invention comprises a chestpiece of theinvention, a binaural tubing, and an earpiece assembly mechanicallyconnected to provide an acoustic pathway from the chestpiece to thebinaural tubing to the earpiece assembly.

Another aspect of the invention preferably provides placing thetransducer in a coaxial position within the acoustic pathway in thechestpiece. More preferably, the coaxial position of the transducer isconcentrically within the acoustic pathway.

Another aspect of the invention preferably provides placing thetransducer in a mounting within the acoustic pathway of the chestpiecein which the mounting has shock attenuating or vibration isolatingproperties. More preferably, the mounting provides three degrees offreedom of motion of the transducer within chestpiece to minimizeambient sound pickup from vibration or mechanically transferredacoustical energy.

A feature of the invention is the positioning of the transducer withinthe same stream of sound as is heard by the health care practitionerwhen using the conventional acoustic stethoscope.

Another feature of the invention is the minimizing of the number ofpathways for sound to be received within the chestpiece, therebyminimizing distortion of the acoustic signals.

An advantage of the invention is that the health care practitioner usesthe same pathway of sound to receive both acoustically transmittedinformation and electrically generated information from the stethoscopechestpiece.

The foregoing advantages, construction and operation of the presentinvention will become more readily apparent from the followingdescription and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a stethoscope incorporating the featuresof electronic pickup enhancement.

FIG. 2 is a cross-sectional view of the chestpiece incorporating adetachable stem.

FIG. 3 is a exploded view, in partial cross-section of the stem showingthe transducer, transducer mounting, and cable strain relief therein.

FIG. 4 is a cross-sectional view of the chestpiece and the stem showingthe transducer, transducer mounting, and cable strain relief inassembled position.

FIG. 5 is a partial cross-section of the transducer and transducermounting in spatial orientation.

EMBODIMENTS OF THE INVENTION

The stethoscope 1 of the present invention illustrated in FIG. 1 has achestpiece 10 which is easily grasped by the health care practitionerand fits comfortably into the practitioner's hand.

Chestpiece 10 is adapted to receive auscultatory sounds from the bodyand adapted to transfer such sounds through an acoustic pathway withinchestpiece 10 and to binaural tubing 11 which is mechanically andacoustically coupled to an earpiece assembly 13 for contact with theears of the user. Earpiece assembly 13 has two earpiece tubes 15 and 16extending from a yoke (not shown) in binaural tubing 11 and adapted tofit in or near the ear of a user. Tubes 15 and 16 terminate in eartips17 and 18, respectively, for a comfortable fit for the user.Stethoscopes generally are described in U.S. Pat. No. 4,200,169(MacDonald, III et al.); U.S. Pat. No. 4,440,258 (Packard); U.S. Pat.No. 4,475,969 (Packard); U.S. Pat. No. 4,913,259 (Packard et al.); U.S.Pat. No. 5,111,904 (Packard et al.); and copending, co-assigned U.S.patent application Ser. No. 07/658,099 (Dieken), now U.S. Pat. No.5,204,500, the disclosures of which are incorporated by referenceherein.

Within chestpiece 10 is an acoustic to electrical transducer, (as seenin FIG. 4), which is connected to electrical connector 12 by means of anelectrical cable (not shown). Electrical connector 12 serves as anelectrical link to an auscultation system other than acousticauscultation, such as those described in U.S. Pat. No. 5,010,889(Bredesen et al.) and pending U.S. patent application Ser. No.07/782,079 (Bredesen et al.), now U.S. Pat. No. 5,213,108, thedisclosures of which are incorporated by reference.

The acoustic pathway within chestpiece 10 is shown in FIG. 2. Chestpiece10 includes a chestpiece housing 20, a stem 22, and a chamber 24 adaptedto receive sounds transmitted by a diaphragm 27. An acoustic pathway 25in the chestpiece proceeds from diaphragm 27 into chamber 24 and intohollow, preferably detachable, stem 22. Diaphragm 27 resides inchestpiece housing 20 in a manner as taught by U.S. Pat. No. 4,475,619(Packard). If stem 22 is detachable, stem 22 is detachably secured tochestpiece housing 20 by set screw 26 as illustrated in FIG. 4.

Transducer 34 is located within the acoustic pathway 25 of stem 22,communicating electrically with connector 12 through cable 31 comprisingwires of about 32 AWG. Preferably, transducer 34 is held within theacoustic pathway 25 using a mounting 35 which has a collar portion 40,preferably adapted to seal environmental sound from entering theacoustic pathway 25 through the interface between stem 22 and chestpiecehousing 20.

Cable 31 is physically restrained from placing mechanical force on thetransducer 34 by stress relief comprising cable clip 38 secured to thecable 31, a spacer 37 around the cable 31, and a knot 36 in the cable31. Spacer 37 is interference fit into stem 22. This strain relief andfine gauge wire previously mentioned provide secure positioning of thecable 31, without mechanically stressing the electrical connections, butwith minimal mechanical transfer of environmental vibrations to thetransducer.

Mounting 35 causes transducer 34 to be positioned, preferably coaxially,within the same acoustic pathway 25 as employed for acousticauscultation through binaural tube 11 to the user and for the transducerto receive unobstructed contact with the stream of sound that is alsoheard by the user. More preferably, the transducer is concentricallypositioned within the acoustic pathway 25. At least one opening 39resides in mounting 35 in location(s) around transducer 34 permitpassage of sound in the pathway 25 past transducer 34 and into theremainder of stem 22 and thence to binaural tube 11 and to the ears ofthe user.

Mounting 35 can be made from a range of elastomeric materials to provideflexibility for the positioning of transducer 34 in the acoustic pathway25. Such flexibility can provide the very desirable advantage of shockattenuation or other vibration isolation for the transducer 34 withinthe stethoscope chestpiece 10.

Preferably, mounting 35 is molded from silicon rubber molding materialhaving a Shore A durometer of about 20-50, and preferably about 40 ShoreA. The durometer scale of hardness-softness is defined by the Shoresystem of measurement and adopted as ASTM Standard D2240. Such rubbermaterial is commercially available from General Electric Company,Schenectady N.Y.

Transducer 34 can be any transducer which is capable receiving soundwaves and changing such waves into electrical signals. Nonlimitingexamples include pressure transducers and microphones. Presentlypreferred for transducer 34 is Panasonic model WM-063Y microphone fromPanasonic of Secaucus, N.J.

The flexible positioning of transducer 34 within acoustic pathway 25using mounting 35 of elastomeric material minimizes the conversion ofextraneous sound into electrical signals by the transducer 34. Vibrationor environmental sound can be introduced to a chestpiece in all spatialdirections. Three degrees of freedom of motion for transducer 34 withinmounting 35 are illustrated in FIG. 5. Isolation through constrainedmotion in each of the X, Y, and Z directions is controlled by theconfiguration of the mounting 35 as shown in FIG. 5 and the use of aflexible material for mounting 35. This flexibility of mounting 35 inthree orthogonal directions attenuates shock and other sound-inducingvibrations, thereby isolating, to the maximum extent possible, thetransducer 34 from all sounds other than the sound passing within theacoustic pathway 25.

While the embodiments of the invention have been described, theinvention is not limited thereto. The claims of the invention follow.

What is claimed is:
 1. A stethoscope chestpiece for transmittingauscultatory sounds both acoustically and electrically, comprising:astethoscope housing forming an acoustic pathway for acousticauscultation; a mounting having at least one opening to permit passageof sound in the acoustic pathway; and an acoustic to electricaltransducer residing within the mounting and within the acoustic pathwayand positioned within the same acoustic pathway as employed for acousticauscultation, wherein the transducer resides coaxially within theacoustic pathway; whereby the same pathway of sound is used to receiveboth acoustically transmitted information and electrically generatedinformation from the stethoscope chestpiece.
 2. The stethoscopechestpiece according to claim 1, wherein the transducer resides withinthe mounting in a stem of the chestpiece isolating the transducer fromvibration.
 3. The stethoscope chestpiece according to claim 2, whereinthe mounting comprises an elastomeric material.
 4. The stethoscopechestpiece according to claim 3, wherein the mounting provides threedegrees of freedom of motion for the transducer within the acousticpathway.
 5. The stethoscope chestpiece according to claim 4, wherein thestethoscope housing comprises a detachable stem, and wherein themounting further comprises a collar portion engaging the detachable stemand the stethoscope housing, whereby a seal from environmental sound isprovided.
 6. The stethoscope chestpiece according to claim 4, whereinthe mounting positions the transducer concentrically within the acousticpathway.
 7. A stethoscope comprising a chestpiece of claim 1, a binauraltubing, and an earpiece assembly mechanically connected to provide acontinuous acoustic pathway from the chestpiece through the mounting andthrough the binaural tubing to the earpiece assembly, wherein the tubingfurther comprises an electrical connector in electrical communicationwith the transducer.
 8. The stethoscope according to claim 7, whereinthe transducer resides coaxially within the acoustic pathway.
 9. Thestethoscope according to claim 7, wherein the transducer resides withinthe mounting in a stem of the chestpiece isolating the transducer fromvibration.
 10. The stethoscope according to claim 9, wherein themounting comprises an elastomeric material.
 11. The stethoscopeaccording to claim 10, wherein the mounting provides three degrees offreedom of motion for the transducer within the acoustic pathway. 12.The stethoscope according to claim 11, wherein the stethoscope housingcomprises a detachable stem, and wherein the mounting further comprisesa collar portion engaging the detachable stem and the stethoscopehousing, whereby a seal from environmental sound is provided.